The present invention relates generally to joining systems and, more particularly, to a method of forming joining profiles in structural frames such as metallic frames having a channel shaped cross section. Such structural frames may be used in the construction of wall assemblies such as partitioning walls and curtain walls.
In building construction, conventional wall fabrication techniques employ the use of upper and lower headers that are disposed in spaced relationship to one another. The upper and lower headers may be attached to the ceiling and floor portions of a building structure and are interconnected with a plurality of stud members disposed in spaced, parallel relationship to one another. The stud members are typically connected to the top and bottom headers with mechanical fasteners such as nails, screws and the like.
The framing, which is comprised of the upper and lower headers and the stud members, may be of wooden or metallic construction. Panels such as drywall, gypsum board, sheetrock, and the like are then installed on opposing sides of the framing in order to complete the basic wall structure. Unfortunately, traditional wall construction suffers from several drawbacks include the time consuming nature of such traditional wall construction methods and resultant high costs.
Metallic framing systems typically employ the use of lightweight steel stud members which are generally channel shaped or U-shaped. The stud members are attachable at opposing ends to horizontally oriented top and bottom members. The top and bottom members are, in turn, secured to the building structure adjacent the ceiling and floor. In this regard, a metallic framing system comprises a series of spaced apart steel stud members engaged to the top and bottom plate members and which includes wall board which is attached to opposing sides of the metallic faming system.
In conventional construction methodology, the frames may be assembled on the ground with the top and bottom members being disposed in spaced apart relationship. The stud members are then connected to the top and bottom members by engaging the ends of the stud with screws or other suitable fasteners. Because the metallic framing system is dependent upon fasteners for interconnecting the stud members to the top and bottom members, the framing system is generally structurally weak when the stud members are initially engaged to the top and bottom members prior to fastener installation. The framing system does not achieve full strength until wall board is affixed to the frame and therefore provides insufficient rigidity until fasteners are inserted.
Another method of securing the stud members to the top and bottom members involve the use of a tab and slot arrangement wherein tabs disposed on extreme ends of the top and bottom members engage corresponding slots in the stud members. Such engagement is facilitated by manually urging (i.e., with a hammer) the tabs so that they are reoriented at an angular orientation relative to the stud members which thereby locks the stud members against the top and bottom members.
Unfortunately, such method of interconnecting the stud members to the top and bottom members requires additional material to form the top and bottom members. Furthermore, the reorienting or bending of the tabs into the locking position requires additional labor and is therefore relatively time consuming. Although the tab and slot method of connecting the stud members to the top and bottom members is generally effective in securing such members, the amount of time required to bend the tab a total of four times for each stud member represents a significant drawback which detracts from the overall utility of this type of metallic framing system.
Another method of constructing a metallic framing system from stud members and top and bottom members involves the use of cooperating formations in each of the components. The formations consist of a securing notch formed in the walls of the mating stud member and top and bottom members. In order to facilitate the positioning of the stud member, the walls of the top and bottom members include an upturned lip formed at a location where the stud member mates with the top and bottom members.
Unfortunately, the additional materials required to form such lip increases overall material costs and necessitates the use of a securing clip which further adds to labor and assembly costs. Another drawback associated with such methodology of connection is the low strength of the framing system due to the minimal amount of engagement between the mating components. More specifically, the limited engagement between the mating components minimizes the overall resistance of the framing system to rotation, twisting and separation of the stud member and top and bottom plate members.
Another problem associated with prior art metallic framing systems is a result of irregularities in floor to ceiling heights. More particularly, in building construction, poor concrete finishing and/or irregularities in the height of the ceiling structure necessitates the time-consuming task of cutting and fitting individual stud members to fit between the top and bottom members mounted to the ceiling and floor. Ideally, the spacing between the floor and the ceiling structure is preferably constant such that the stud members may generally be of the same length.
However, irregularities in spacing often occur such that each of the stud members must be custom fit. Furthermore, windows and/or doors installed in many wall structures require that the stud members must be cut and fit on a trial-and-error basis to accommodate the specific window or door size. In other words, a plurality of custom-fit stud members must be first cut to an approximate length and test-fit and then often trimmed in order to form the framing above and below the windows and/or doors. As may be appreciated, such individual cutting, fitting and trimming of the stud members is time consuming and adds additional labor costs to the overall wall installation.
A further deficiency associated with conventional wall structures is the rigid or non-adaptive nature of the wall structure to changes in ceiling height as a result of settling of the building foundation and/or building movement such as may be caused by seismic activity or creeping of load-carrying beams in the building structure over time. The same drawbacks described above associated with relative movement between the framing system and the wall board is present in ceiling movement or building settling.
As can be seen, there exists a need in the art for a method of producing joining profiles in metallic framing for a wall structure such that structural members which make up the metallic framing may be securely fastened in a convenient and time efficient manner. It should be pointed out that it is well known in the art that relatively thin or light gauge steel is particularly prone to tearing and unwanted deformation during manipulation or forming thereof. In the case of producing joining profiles in light gauge steel, simultaneous stretching and compression operations are performed on different planes of a structural member.
The combined effects of the conflicting stretching and compression forces during forming of a joining profile greatly increases the propensity of the steel material to tear and produce unwanted deformations. Therefore, there exists a need in the art for a method of introducing such joining profiles in structural members fabricated of light gauge steel which overcomes propensities for unwanted tearing and deformation during simultaneous stretching and compression of the structural members. Furthermore, there exists a need in the art for introducing joining profiles via a method that provides for the manipulation of light gauge structural steel members at very high speeds such that such structural members may be mass-produced quickly, economically, and efficiently.